Birth-order effects in the academically talented

Birth-order position was studied among 828 academically talented students from a national sample collected by the Institute for the Academic Advancement of Youth of Johns Hopkins University. When compared to 1990 U.S. Census Bureau data, this sample was disproportionately composed of first-born students. However, much of this birth order effect can be explained by the covariate of family size, with small families overrepresented among the gifted. First-born students tended to get higher verbal scores on the secondary School Admissions Test while youngest-born tended to do better in math. Students were administered the Rotter Internal-External Locus of Control Scale, the Rosenberg Self-Esteem Scale, the Multidimensional perfectionism Scale, the Adjective Check List, the NEO Five Factor inventory, the Myers-Briggs Type Indicator, and the Brief Symptom Inventory. Except for a mild relationship between birth order and perfectionistic type, there was no relationship found between birth-order position and personality and adjustment. It is believed that often reported birth-order position effects are strongly related to the covariance of family size.